.start{
    position: relative;
    .banner{
        width: 100%;
        height: 100vh;
        image{
            width: 100%;
            height: 100%;
        }
    }
    .btn{
        
        position: absolute;
        left: 50%;
        bottom: 20px;
        margin-left:-50px;
        width: 100px;
        height: 30px;
        display: flex;
        justify-content: center;
    }
}